1. Field of the Invention
The present invention relates to an appartaus for preserving the contents of a part-filled beverage bottle and to a stopper for a beverage bottle for use in the apparatus.
2. Background Information
Wine and champagne in part-filled bottles oxidise under the oxygen present in the normal ambient air, resulting in a rapid loss in quality. In the case of champagne, the natural liquid-bound CO2 additionally escapes into the environment, making the champagne go flat which is likewise most undesirable.
U.S. Pat. No. 5,215,129, for example, discloses a system for preserving the contents of part-filled beverage bottles where the part-filled bottles of wine and champagne or sparkling wine are provided with a special stopper which either has an integrated non-return outlet valve (for wine bottles or generally for bottles with a so-called xe2x80x9cstillxe2x80x9d content) or an integrated non-return inlet valve (for champagne and sparkling wine). The system has an application head to which the bottle stopper can be coupled in close communication when approached thereto. For wine bottles, the application head is an evacuation head which is connected to a suction pump. For champagne and sparkling wine bottles the application head is a charge head which is connected to a pressure pump. In a special embodiment the application head is both an evacuation and a charge head and is correspondingly connected to a suction and a pressure pump. When a bottle with the special stopper fixed thereto is coupled to the application head then, depending on whether the bottle is a wine bottle or a champagne or sparkling wine bottle, a control starts either the suction pump or the pressure pump and, in the case of wine, sucks air from the bottle via the outlet valve integrated in the stopper or, in the case of champagne or sparkling wine, presses air or CO2 into the bottle via the inlet valve integrated in the stopper. Accordingly, subatmospheric pressure is created in the case of wine or still beverages, and superatmospheric pressure is created in the case of champagne or sparkling wine.
EP-A-0 234 607 discloses a similar but simpler system only for wine or other still beverages which likewise uses a special stopper but where the evacuation of the part-filled bottle closed with the special stopper is carried out by means of a hand pump.
Although the known systems preserve the quality of the beverages in the part-filled bottles for a relatively short period of time they cannot meet, in particular, high quality demands.
Starting from this state of the art, it is accordingly the object of this invention to improve the preservation of the quality of the contents of part-filled beverage bottles, the aim being not only to achieve, in particular, an prolongation of the preservation of the quality as compared to the customary methods but also to keep the per se unavoidable quality loss ensuing already from the opening of the bottle as small as possible.
According to the fundamental ideas of the present invention the gas volume above the liquid level in the beverage bottle is thus flushed and filled with nitrogen or a similar food-compatible gas and the bottle is then tightly closed and preferably kept under a slight overpressure. This brings the residual oxygen above the liquid level in the bottle down to the greatest possible minimum and the quality loss after the first opening of the bottle is thus virtually completely prevented even over an extended period of time.
Most suitable for expelling the ambient air or residual oxygen above the liquid level from the bottle is food quality nitrogen N2. Nitrogen does not diffuse in liquids and therefore does not affect the taste of the liquid, wine or champagne. Nitrogen is available in sufficient amounts and at favourable conditions and can be transported and stored without danger.
FR-A-2 526 762 discloses a bottle stopper which can replace conventional corks in the necks of, for example, wine bottles in order to preserve their contents. This bottle stopper contains an exchangeable cartridge with nitrogen which is under pressure. Through the exertion of pressure on a control button an inlet valve in the stopper is opened through which nitrogen streams from the cartridge into the bottle. The air present above the liquid level in the bottle is expelled by this and is led out through the venting channels provided in the stopper. In the venting channels there are overpressure valves which are closed under normal atmospheric pressure. The replacement of air with nitrogen preserves the bottle contents.
U.S. Pat. No. 4,702,396 discloses a similar bottle stopper which is additionally a dispenser. In this case the nitrogen pressure cartridge, which is likewise exchangeable, is in constant communicating connection with the inside of the bottle, in the neck of which the stopper is inserted, via a pressure regulator and an inlet pipe and creates an overpressure in the bottle which is employed on the one hand to expel the air above the liquid level and on the other hand to withdraw the bottle contents. The air escapes through a vent pipe which is fitted with an outlet valve which can be opened manually. The liquid in the bottle flows out through a rising pipe reaching down to the bottom of the bottle and in which there is an output valve which can be manually operated.
Although the bottle stoppers described in FR-A-2 526 762 and in U.S. Pat. No. 4,702,396 are capable of preserving the contents of part-filled bottles, they are relatively complicated as stoppers and are therefore uneconomical for common use.